NOVEL DIFFERENTIAL ULTRA-VIOLET RESONANCE ABSORPTION GAS ANALYZER FOR NOX MEASUREMENTS IN CONTINUOUS EMISSION MONITORING SYSTEMS

摘要

Differential Resonant Absorption Ultra-Violet Spectroscopy (DUV-RAS) basedrnanalyzers have potential to replace chemiluminescent analyzers in Continuous EmissionrnMonitoring Systems (CEMS). Due to the demanding analytical requirements and thernadvantages offered by the DUV-RAS analyzers, this new approach provides superiorrnemission data at lower costs. Advantages include low noise, no water and carbon dioxiderninterference, less equipment for operation, and reduced costs. Although thernchemiluminescent analyzer offers the benefit of wide measuring ranges down to lowrnconcentrations with a fast response time, its drawbacks are characterized by quenchingrneffects caused by carbon dioxide and water, by an adverse cost-benefit ratio, by the factrnthat ozone, a highly toxic gas is required and by additional components needed, such asrnvacuum pumps and deozonizer. As the levels of NOx are becoming lower and lower in